a) Field of the Invention
The invention relates to an arrangement for moving material to be conveyed along a conveying plane, in particular for freight-loading systems in freight compartments, preferably of aircraft.
b) Description of the Related Art
So-called roller drives, which are fully described in German Patent 41 36 972, are known for the transport of loads in aircraft freight compartments. In this case, a conveying roller, which is connected to a drive, is controlled in its rolling motion by virtue of the fact that sensors detect the position of material to be transported above the conveying module driving the conveying roller and thus switch the drive on or off as required. A disadvantage in this case is that there are no measures for realizing different pressure forces. However, these are necessary in order to be able to safely move and/or stop all sorts of freight and to design such a drive in such a way that it is safe in operation and functions free of maintenance for long operating periods.
Furthermore, DE 196 08 236 C1 has disclosed a roller drive unit for the transport of freight containers in which the drive roller is simultaneously lifted, by the motor driving the drive roller, by means of a cam and pressed against the material to be conveyed.
A roller drive unit described in DE 39 11 214 C3 works in a similar manner, which roller drive unit, by means of an intermediate gear running in the roller interior and having a braking device, taps the pressure force from the drive motor, the drive axis of which lies eccentrically in the roller interior relative to the roller. In this type of conveying roller drive, the pressure force depends on the rotary drive of the conveying roller, as a result of which the pressure force cannot be set to a value suitable for the respective material to be conveyed. The consequences are increased wear and a relatively short operating period.